If OnePlus co-founder Carl Pei was trying to be slick about using the new OnePlus 5 phone — especially before its speculated summer release — well, he didn't do that great a job of hiding it from us.

In a leak over the weekend, Pei was story-ing away on his Instagram account, when Twitter user @LifeofSM noticed that the phone maker wasn't using his usual OnePlus 3T. Instead, the observant user noticed that Pei flashed a much different type of phone than any he'd ever seen Pei use, teasing us with speculation about what that could mean for the OnePlus lineup.

Pei's blurry reflection of the OnePlus 5 shows a couple of interesting features. It kinda looks like the new smartphone could have a triple rear camera. Though, in my opinion, it looks like the phone will have a dual rear camera. The third cutout doesn't look to be a camera at all, but looks to be more in the shape of a fingerprint. This could mean that the OnePlus 5 could have a rear fingerprint sensor, differing from all previous OnePlus models which have the fingerprint sensor on the front.

The phone appears to be in a bulky case that was made to obscure features and design, so nothing is certain as of now. Dallas Thomas, writer and editor for Gadget Hacks, believes that Pei wouldn't put a fingerprint sensor on the back for design reasons:

I'm skeptical this is a rear-mounted fingerprint sensor considering the dimensions of past OnePlus flagships and how high up on the back that the third circle is. If it truly were a fingerprint sensor, it would be even more difficult to use than the awkwardly-placed sensor on the back of the Galaxy S8.

The dual cameras on the back could mean a number of things. There could be potential for unpixalated zoom shots or switching between different lenses. Based on the quality of Pei's Instagram photos, the co-founder is pretty serious about taking good quality images. This could mean that the OnePlus 5 is being created with the idea of photography in mind.

Whether or not OnePlus users will accept a rear fingerprint sensor remains to be seen. Though, there already are some pretty disappointed speculations from users on Twitter. Many are already hoping that the third cutout won't turn out to be a fingerprint sensor. Based on Pei's images though, it does really look like the fingerprint sensor or something besides a third camera, will indeed be on the back.

My money's on a dual-camera layout with a cluster of related instruments being the third circle (camera flash, laser auto focus, etc.).

— Dallas Thomas in a statement to Gadget Hacks

Check out our full OnePlus 5 rumor roundup below and stay tuned for continual updates on the phone before its anticipated summer release.